Gardaí are preparing a report for the Justice Minister after it was reported a member of the force sent a text message to a paramilitary in Northern Ireland.
It is claimed the garda was working at a station in Leinster where two dissident suspects were being questioned.
A spokesperson for the Gardaí confirmed they were investigating the matter and that a full report will be provided to the Justice Minister .
Minister Frances Fitzgerald said she was disturbed by the reports and wanted the facts to be established urgently.
It is not known whether the garda has been suspended, pending the outcome of the investigation.